Anomalous or aberrant movement of a reciprocating element in a reciprocating device poses a number of potential problems, ranging from decreased efficiency of the device to catastrophic failure of the device, with the potential for attendant harm to both people and property. While such anomalous or aberrant movement is known to produce vibratory signals, use of such signals to diagnose the cause, type, or extent of the anomalous or aberrant movement has, to date, been largely unsuccessful.